Knitting machine for producing cut pile fabric



w; J. KELLY 2,892,331

.KNITTING MACHINE FOR PRODUCING CUT FILE FABRIC June 30, 1959 FiledApril 23, 195'? m wE United States Patent KNITTING MACHINE FOR PRODUCINGCUT PILE FABRIC Walter J. Kelly, Amsterdam, N.Y., assignor to MohascoIndustries, Inc., Amsterdam, N.Y., a corporation of New York 7Application April 23, 1957, Serial No. 654,526

. 1 Claim. (Cl. 66-85) This invention relates to knitting machines ofthe warp type, which are provided with means for engaging weft yarns andholding them to form pile loops on the face of the fabric as theknitting proceeds. More particularly, the invention is concerned withimproved means for use on a warp knitting machine, which holds weftyarns laid successively thereon to form pile loops and operates, after aplurality of loops have been so formed, to sever the loops one at a timeand thus convert each loop mto a pair of pile tuft legs. Theloop-severing means of the invention may be employed in knittingmachines in WhlCh the needles reciprocate in either a vertical or ahorizontal plane, but, for purposes of explanation, the application ofthe invention to a machine having vertical needles will be illustratedand described in detail.

For better understanding of the invention, reference may be made to theaccompanying drawing in which Fig. 1 is a vertical cross-sectional viewthrough part of a knitting machine provided with the new loop-cuttingmeans;

Fig. 2 is a fragmentary plan view showing parts of the machine andcutting mechanism; and

Fig. 3 is a fragmentary elevational view showing the action of the shearblades.

The loop-cutting means of the invention is illustrated in Fig. 1 inassociation with a knitting machine of conventional construction, whichcomprises a vertical trick plate having a head 11 with spaced verticalslots for the needles 12. The needles shown are of the ordinary latchtype and they are mounted in the usual way in leads 13 carried by a bar,which is reciprocable to move the needles up and down during theknitting operation. The machine is provided with a plurality of sets ofyarn guides 14, 15, 16 and the guides of each set are carried by bars,such as the bar 17. The several bars are mounted for swinging movementtransverse to the row of needles and are also capable of being shoggedendwise in the usual way. The guides 14 handle the warp yarns W, ofwhich the chain stitches are made, while the guides 15 are for the pileweft yarns P, and guides 16 for the back weft yarns B. When the bars areswung, the lower ends of the guides describe circles below the level ofthe tops of the needles when the latter are in their top position.

In order to form loops of the pile tuft yarns, the machine is providedwith a set of stationary plush points 18, which are mounted on a bar 19and lie in the planes of respective needles. Each plush point has ahorizontal or base portion 18a and an inclined vertical portion 18b andthe portions 18b of the plush points are spaced from the trick plate bya distance, which depends upon the length of the loops to be formed. Thebar 19 carrying the points is mounted on the knitting machine in anyconvenient manner, and, in the construction illustrated, the bar issecured to the vertical flange of an angle iron 20 carried by themachine frame.

The horizontal flange of the angle iron 20 carries a number of bearingblocks 21 for a rock shaft 22 formed with spaced flat surfaces, to whichthe lower end of arms 23 are bolted. The arms are secured near theirupper ends to thevertical flange of an angle iron 24, the horizontalflange of which supports a bar 25, on which a plurality of cuttingblades 26 are mounted. There is one blade 26 for each of the plushpoints 18 and the forward cutting edge 26a of each blade 26 slopesupward and away from the plush point at an angle. The blades 26 are sopositioned as to bear against the sides of the horizontal portions 18aof their respective plush points and the cutting edge of each bladeprojects above the top of the horizontal portion of its related plushpoint, as shown in Figs. 1 and 3.

At its upper end, each arm.23 carries a pivot pin 27, on which ismounted one end of a link 28 having its other end connected pivotally toa lever 29 pivoted on a part of the machine frame. The lever has aroller 30 hearing against the surface of a cam 31 on a shaft 32supported for rotation on the machine frame, and a spring 33 connectedat one end to an ear 29a on the lever and at the other to a bracket 34on an angle iron 35 attached to the machine frame, tends to swing thelever clockwise and maintain roller 30 against the surface of the cam.

In the operation of the knitting machine, the needles reciprocatevertically in the usual way and the yarn guides 14, 15, 16 are swung andshogged relatively to the needles. In these operations, the warp yarnguides 14 lay the warp yarns W around the individual needles so that,when the needles descend, chain stitches will be formed. Each of theguides 16 is swung across two or more needles and lays its yarn Bagainst the back of the needles, so that the back weft yarns are caughtin the chain stitches and serve to connect the stitches together andform a fabric. The guides 15 for the pile yarns P are shogged, when theguides lie at the back of the plush points and remote from the needles,and each guide 15 is shogged past one needle only, so that, on thereturn swing of the guide, its yarn will be wrapped about the plushpoint associated with the needle. As the result of this action of theguides 15, a succession of loops of pile yarn is laid on each of theindividual plush points 18.

In each cycle of the knitting machine, cam 31 makes one revolution andacts through lever 29 and link 28 to cause the bar 25 to move thecutting blades 26 toward the plush points and back. As the loops of pileyarn (are formed successively on the plush points, the loops travel downthe respective points in succeeding knitting cycles, until the leadingloop of each series on a plush point lies in the angle between thehorizontal portion 18a and the vertical portion 18b of the point. Whenthe loop arrives at this place, the blade 26 associated with the plushpolnt moves forward and severs the loop. In its movement, the bladeengages the side of its associated plush point and cuts the loop with ashearing action, in which the edge of the plush point along the sides ofthe angle between its vertical and horizontal portions cooperates wlththe cutting edge at the forward end of the blade, as shown in Fig. 3. Atthe time of the cutting operation, two other loops of yarn lie above thelowermost one, but the inclination of the cutting edge 26a of each bladeand the length of its stroke are such that, when the blade makes acutting stroke, it severs only the lowermost loop. The two loops left onthe point move down a step in the next cycle so that, when the bladesagain move forward, another loop is in position to be cut. By thusretaining a number of loops on each plush point and cutting only thelowermost loop, the uncut loops are held taut so that their ends can beproperly anchored in the stitches of the fabric with the loops at fulllength.

As the knitting operation continues, the knitted fabric travels down thevertical face of the trick plate with the tuft legs T formed by thecutting of the loops passing between the blade end and the verticalflange of the angle iron 20. 'Thefabric is taken up in the usual way andis ultimately finished by the shearing of the upper ends of the legs ofthe cut loops to form a pile of uniform height.

I claim:

"In a warpknitting machine"having a row of reciprocable needles,1a' setofguidesoperating to lay warp yarns about the'needles' to enable theneedles to knitchains of stitches 'of theyarns,and sets ofguides'movable transverselyand lengthwise of the row'of" needles to layback weft yarns and pile weft yarns, respectively, in the stitches ofthe chains, thecombination of a plurality of stationary plushpointslying parallel to and in the planes of respective needles and extendingfrom'one side of the paths of travel of the pile yarn guides'to. theother in position to hold a seriesof pile yarn loops laid successivelythereon by said guides, each plush point havinga loop-receivingportion-lying substantially'parallel'to the needles and a baseportion"lying at an angle'toithe loop-receiving portion and extending away fromthe row of needles, blades movable along and in contact with respectivepoints, each blade having a cutting edge =at its forward end extendingobliquely relative to the direction of movement of the blade and thecutting edge of each blade being adapted to co-operate with the edgeofits associated plush point between the loop-receiving and base portionsof the plush point to sever the inmost loop of pile yarn von theloopreceiving portion of the plush point with a shearing action, andmeans for moving said blades relative to their associated points tosever pile yarn loops on the points.

References Cited in the file of this patent UNITED STATES PATENTS

